Boiler



June 2, 1936. T. E. MURRAY BOILER Filed May 31, 1923 v 23 O 21 2O 2 Sheets-Sheet 1 3mm Flo/m5 /VOPRAY June 2, 1936. T. E. MURRAY BOILER Fi led May 31, 1923 2 Sheets-Sheet 2 Patented June 2, 1936 UNITED STATES PATENT OFFICE 2,042,012'.

Thomas E. Murray, New York, N. 1.: Joseph Bradley Murray, Thomas E. Murray, John F. Murray,. executors of said Thomas E.

assignors to Metropolitan Company, a corporation of New Murray, deceased, Engineerin York Appllnaflonflaytl, 1923,8erlalNo. 042,421 4 Glaiml- (01. 122-235) This invention relates to boilers and particu larly to the construction of boiler walls and boil er furnace walls.

In the accompanying drawings- Figure .1 is a perspective view of the boiler partly broken-away; I

Figure 2 is a diagrammatical longitudinal section of the same;

Figure 3 is a vertical section of 'a detail; and Figure 4 is a horizontal section of the same. Referring to the embodiment of the'invention illustrated, the boiler comprises side walls "I 4 joints.

and I2, a front wall II and rear wall l6, and a top wall or root l8.

The side walls Ill and 12 are formedof a series of upright units comprising tubes 20 metal extensions such as the flanges 2|, for in,- stance, Fig. 4, welded to the tubes or otherwise attached thereto with good heat conducting Inner curved portions 22 partly overlying the tubes facilitate such a welded connection.

The tubes 20, are connected into the circulation of the generator, communicating at the top and bottom, respectively, and 24.

The rear wall It of the boiler is formed of a multiplicity oi-upright tubular sections 25 which in be similar to the members 20, 2|,or may be or nary tubular headers, and which are united at the t p anfid bottom to transverse headers. and 46, (Fig. ing the front wall It are connected at the top to a header 48, and at the bottom to a header 50 by communicating nipples or other suitable connection, The header 5B is elevated to leave an openwith hollow headers 23 ing for the entrance of a known typcof stoker.

Instead of such stoker; the boiler can be fired manually, in which case doors, not shown, will be provided. The boiler may be provided with a suitable grate diagrammatically shown at 58, Fig. 2,-and bridge wall and boiler tubes 62 extending approximately horizontally overhead and heated chiefly by convection. The tubes 62 communicate at their opposite ends with the hollow header members 25 and 26. Suitable bailles 64, such as tile, water tubes or brickwork, are secured in known manner to theboiler tubes so as to cause the products of combustionto followa sinuous path through the boiler, A flue opening ing to the stack. I

The tubular side walls are combined with an outer layer or covering of refractory material,

such, for example, as the layer or sheathing 1'4 with lateral The hollow members 26 form-" fire doors and ash pit under modern high 56 is formed in the roof, leadof plastic insulating material held in place by a reinforcement of woven wire mesh 16 which is The boiler tubes 62 may be of the usual round Russo-ac shape secured to the hollow headers 25 and 26; 4

these being provided with openings opposite the ends of the tubes, which openings are closed by suitable plugs 18. The upright hollow corner tubes 19 are provided with plugged openings whichgive access to the interior. lugs and plugs may be used in' the various members for insertion of tools in assembling, or'for cleaning sediment or scale.

The feed water may more points and for, this purpose, I have shown in Fig. 1 a pipe 84 entering the lower header 24. Similar feed pipes may be located atthe opposite side of the boiler,'or the feed water can be supplied froma common header to several of the tubular members 20.

The boiler walls may be supported in the usual manner on a floor or other foundation. Or walls of the kind described can be hung or suspended from the structural beams or girders in a power house or other. building.

- steam at a rate of several hundred per cent of the usual rating based on area exposed to the heating gases and requires for this result a high volume of intensely hot gas.v It becomes important therefore to prevent-the exposure of the usual masonry wall to the fire. Experience shows that such walls are rapidly deteriorated temperature firing. The metal fillers or extensions of my improved boiler forma shield which protects any outside sheath- Similar opening, the tubes with the metal fillers or extensions constituting in effect: a wall of the combustion chamber so that the plastic material'on the outtense heat of the flame and which have a comside may be a mere insulating sheathing sup- I boilers (that is, steam generators as distl ported by the wall of tubes and fillers.

The fillers or extensions have an additonal function to conduct heat to the water tubes so rapidly as to utilize the intense heat of the fire. In installations of this character the distance to which the extensions may be carried beyond the tubes is limited. It must be so short that the heat is conducted to thetubes sufnciently rapidly to prevent the outer portions of the extensions from being burned away or distorted sufliciently to crack them. Such conduction of heat to the tube is aifected by the area and-the degree of contact of the extension member with the tube, but is chiefly dependent on the distance from the tube to the remotest part of the extension. Such distance puts a maximum limitation -on the distance between the tubes in the case of gh duty from mere water heaters or the like).

In practice, I have found that the maximum distance should not be substantially greater than the outside diameter of the tubes. The exten- ,-sions beyond the tube, with such spacing, are of less width than the diameter of the tubes and can be kept within such limits as to avoid de struction by the fire.

Generally in boilers of the type on which the present invention is an improvement, particularly those designed to generate large quantities of steam at high temperature and pressure, the

walls of the furnace support the overhead struconly does this provide for a high capacity approximately horizontal water ture and are made of or lined with refractory brick-work which isexposed directly to the inparatively short life, There are frequent shutdowns for repair or replacement of such, walls. According to this invention the principal part of the, wall is the tubular metal structure. Not

cause of the rapid generation of steam by ex posure of the tubes to the direct radiant heat ofthe burning fuel, but also the life of the wall. cooled by the rapid circulation of water, is practically The insulating material outside of the metal wall is used for the conserving of heat and is protected from excessive wear by the metal structure between it and the fire.

I claim:

1. A steam generator including in combination tubes heated by convection and a furnace having a combustion chamber below said over head tubes, a wall of said combustion chamber being composed of substantially upright tubes connected into the circulation of the generator, said tubes being spaced apart a distance not substantially greater than their diameter, and metal extensions from said tubes united thereto with good heat conductin Joints 5 and practically closing the spaces betwee them but being free to move separately, so that only the tubes and extensions are exposed to the heat of the burning fuel and the two together constitute the wall heated only on its inner face, 10 the other surface of such wall being covered with insulating material.

2. A steam generator including in combination water tubes heated by convection and a furnace having a combustion chamber adjacent to said 15 tubes, a wall of said combustion chamber being composed of water tubes connected into the circulation of the generator, said tubes being spaced apart a distance not substantially greater than their diameter, and metal extensions from said 20 tubes attached thereto with good heat conducting Joints and practically closing the space between them but being free to move separately, so that only the tubes and extensions are exposed to the heat of the burning fuel and the two constitute a wall heated only on its inner face, the outer face of said wall being covered with insulating inatertal. m

3. A stationary steam generator including in combination water tubes heated by convection 9 and a furnace having a combustion chamber, a wall of said combustion chamber being composed of a number of substantially uprightL tubular elements comprising tubes with lateral metal extensions united thereto with good heat conducting Joints, said tubes being connected into the Oil'- culation of the generator and being spaced apart a distance not substantially greater than their diameter and said extensions lying inthe spaces between the tubes and providing an increased 4,0 area exposed to the radiantheat of the burning fuel and condu ng such heat to the tubes, said extensions being ted in width as a maximum to the diameter of the tubes, each element being disconnected from the next but so placed that {6 the tubes and extensions constitute a wall exposed on the inner face only to the radiant heat oftheeombustion gases, the outer surface of such wall being covered with insulating material.

4. The stationary steam generator of claim 3, 69 and means for holding said cover of insulating material against the'outer surface of the wall,

such means being united to the tubular elements composing the wall. THOMAS E. MURRAY. 

